Recast 2017 Financial Information (Details 1) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Product	$ 4,790	$ 4,037	$ 9,079	$ 8,034
Service	2,329	2,436	4,775	4,849
Total sales	7,119	6,473	13,854	12,883
Product	3,694	3,037	6,959	6,020
Service	1,863	1,877	3,768	3,744
General and administrative expenses	739	686	1,450	1,384
Operating income	823	873	1,677	1,735
Interest and Debt Expense	(144)	(76)	(287)	(151)
Net FAS (non-service) Pension Benefit (Expense)	125	(17)	245	(35)
Other, net	45	32	85	51
Earnings before income taxes	849	812	1,720	1,600
Federal and foreign income tax expense	160	257	292	395
Net earnings	$ 689	$ 555	$ 1,428	$ 1,205
Earnings Per Share, Basic	$ 3.95	$ 3.18	$ 8.19	$ 6.90
Weighted Average Number of Shares Outstanding, Basic	174.5	174.5	174.4	174.7
Earnings Per Share, Diluted	$ 3.93	$ 3.16	$ 8.14	$ 6.85
Weighted Average Number of Shares Outstanding, Diluted	175.4	175.5	175.4	175.8
Change in unamortized benefit plan costs, net of tax	$ 86	$ 102	$ 172	$ 201
Change in cumulative translation adjustment	0	(4)	(2)	0
Other, net	3	(1)	4	(3)
Other comprehensive income, net of tax	83	99	166	204
Comprehensive income	$ 772	654	$ 1,594	1,409
Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Product		3,916		7,750
Service		2,459		4,892
Total sales		6,375		12,642
Product		2,958		5,829
Service		1,896		3,783
General and administrative expenses		666		1,343
Operating income		855		1,687
Interest and Debt Expense		(76)		(151)
Net FAS (non-service) Pension Benefit (Expense)		0		0
Other, net		28		44
Earnings before income taxes		807		1,580
Federal and foreign income tax expense		255		388
Net earnings		$ 552		$ 1,192
Earnings Per Share, Basic		$ 3.16		$ 6.82
Weighted Average Number of Shares Outstanding, Basic		174.5		174.7
Earnings Per Share, Diluted		$ 3.15		$ 6.78
Weighted Average Number of Shares Outstanding, Diluted		175.5		175.8
Change in unamortized benefit plan costs, net of tax		$ 102		$ 201
Change in cumulative translation adjustment		(4)		0
Other, net		(1)		(3)
Other comprehensive income, net of tax		99		204
Comprehensive income		651		1,396
Accounting Standards Update 2014-09 [Member] | Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Product		121		284
Service		(23)		(43)
Total sales		98		241
Product		87		208
Service		(14)		(28)
General and administrative expenses		20		41
Operating income		5		20
Interest and Debt Expense		0		0
Net FAS (non-service) Pension Benefit (Expense)		0		0
Other, net		0		0
Earnings before income taxes		5		20
Federal and foreign income tax expense		2		7
Net earnings		$ 3		$ 13
Earnings Per Share, Basic		$ 0.02		$ 0.08
Weighted Average Number of Shares Outstanding, Basic		0.0		0.0
Earnings Per Share, Diluted		$ 0.01		$ 0.07
Weighted Average Number of Shares Outstanding, Diluted		0.0		0.0
Change in unamortized benefit plan costs, net of tax		$ 0		$ 0
Change in cumulative translation adjustment		0		0
Other, net		0		0
Other comprehensive income, net of tax		0		0
Comprehensive income		3		13
Accounting Standards Update 2017-07 [Domain] | Restatement Adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Product		0		0
Service		0		0
Total sales		0		0
Product		(8)		(17)
Service		(5)		(11)
General and administrative expenses		0		0
Operating income		13		28
Interest and Debt Expense		0		0
Net FAS (non-service) Pension Benefit (Expense)		(17)		(35)
Other, net		4		7
Earnings before income taxes		0		0
Federal and foreign income tax expense		0		0
Net earnings		$ 0		$ 0
Earnings Per Share, Basic		$ 0.00		$ 0.00
Weighted Average Number of Shares Outstanding, Basic		0.0		0.0
Earnings Per Share, Diluted		$ 0.00		$ 0.00
Weighted Average Number of Shares Outstanding, Diluted		0.0		0.0
Change in unamortized benefit plan costs, net of tax		$ 0		$ 0
Change in cumulative translation adjustment		0		0
Other, net		0		0
Other comprehensive income, net of tax		0		0
Comprehensive income		$ 0		$ 0